Represents the volume of crude oil.

No definition available.

Name:	int_CrudeOilVolume
Namespace Prefix:	int_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the minimum firm commitments from certain third parties of settlement of funds.

+ References

No definition available.

+ Details

Name:	int_FirmCommitmentsFromCertainThirdPartiesOfSettlementOfFundsMinimum
Namespace Prefix:	int_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the maximum amount the entity has agreed to indemnify for costs and expenses.

+ References

No definition available.

+ Details

Name:	int_IndemnificationOfCostsAndExpensesMaximumAmount
Namespace Prefix:	int_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the number of complaints filed.

+ References

No definition available.

+ Details

Name:	int_NumberOfComplaintsFiled
Namespace Prefix:	int_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of ownership interest in joint venture.

+ References

No definition available.

+ Details

Name:	int_OwnershipInterestInJointVenture
Namespace Prefix:	int_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of ownership interest in joint venture sold during the period.

+ References

No definition available.

+ Details

Name:	int_SaleOfOwnershipInterestInJointVenture
Namespace Prefix:	int_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

+ Details

Name:	us-gaap_AccrualForEnvironmentalLossContingencies
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of known and reasonably estimable amounts of recoveries from third-parties pertaining to an entity's environmental remediation obligations. An entity's balance sheet may include several assets that relate to an environmental remediation obligation. Among them are the following: a. Receivables from other potentially responsible parties that are not providing initial funding; b. anticipated recoveries from insurers; and c. anticipated recoveries from prior owners as a result of indemnification agreements.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Commitments and Contingencies (Details 5) In Millions, unless otherwise specified	12 Months Ended		1 Months Ended						1 Months Ended
	Dec. 31, 2013 item	Dec. 31, 2014 USD ($)	Jan. 31, 2014 Derailment of freight train USD ($)	Jan. 31, 2014 Derailment of freight train CAD	Dec. 31, 2014 Derailment of freight train USD ($)	Jul. 06, 2013 Derailment of freight train bbl	Dec. 31, 2014 Derailment of freight train Accrued expenses and other current liabilities USD ($)	Dec. 31, 2014 Derailment of freight train Other current assets USD ($)	Dec. 31, 2014 DPM	Dec. 31, 2014 DPTS	Dec. 31, 2014 DAKP Derailment of freight train USD ($)
Legal Matters
Membership interest in joint venture (as a percent)									50.00%	50.00%
Volume of crude oil (in barrels)						50,000
Number of complaints filed	20int_NumberOfComplaintsFiled
Minimum firm commitments from certain third parties of settlement of funds			$ 170.0	200.0
Sale of joint venture interest (as a percent)									50.00%	50.00%
Indemnification of costs and expenses, maximum amount											10.0
Liabilities recorded based on estimated losses					40.9		14.8
Receivables for portion of liability recoverable from insurance					38.6			28.9
Estimated amount recoverable due to theft of fuel product		$ 18.0